Specific delivery of a substance to a targeted cell is desirable for various purposes, including pharmacological intervention as well as clinical and research bioassays.
Targeted delivery is particularly desirable where exposure of non-targeted cells to a substance to be delivered is preferably avoided, such as where exposure of non-targeted cells can result in undesirable side effects. For example, a therapeutic intervention may require elimination, inhibition, stimulation and/or activation of a particular cell or cell type. In such a situation, it is advantageous to deliver a substance effective to achieve a desired result preferentially to a targeted cell in order to avoid an undesirable side effect such as inhibition or stimulation of non-targeted cells and cell types. Targeted delivery also allows use of less of the substance to be delivered to achieve a desired effect.
There is a continuing need for compositions and methods for achieving targeted delivery of a substance to a cell.